As Marshfield Police gear up to train and carry Narcan, officers have already used the drug to save a woman’s life.

Narcan, the brand name for nasal naloxone, reverses the effects of opiate overdoses, including heroin overdoses. Police were able to use the drug when responding to a 911 call about a woman not breathing in an apartment complex off Route 139 at 7:04 p.m. Friday, May 2, said Police Chief Phil Tavares.

“This saved a woman’s life,” Tavares said.

Upon arriving at the scene, Officer Michael Gonsalves was met by the victim’s daughter, who brought him to the rear bedroom where her mother was unconscious and not breathing. There were indications the victim had used heroin, Tavares said.

Gonsalves then started CPR. A prescription for Narcan was found in the house, and when Officer Brian Gentry arrived on scene, they were able to administer the Narcan.

“We have not yet begun carrying it and Officer Gonsalves was not trained in it, but read the directions and save the woman’s life,” Tavares said. “This is just the beginning.”

Once the Narcan was used, Tavares said the woman began to breathe on her own and appeared to wake up before emergency personnel took over her care and she was transported to South Shore Hospital in Weymouth.

Narcan acts like an antagonist in the case of an overdose, displacing opiates from the receptors in the brain.

While the fire department already uses Narcan, police are oftentimes the first law enforcement officials on a scene, and carrying the drug allows them to begin life-saving measures even sooner, he said.